This flag allows you to checkpoint a process without its network namespace, ignoring all the devices within. The restart will then depend on either: 1. Userspace recreating the interfaces necessary to rebind sockets 2. The only open sockets are those listening on 0.0.0.0 With this patch, I can checkpoint a network application with this flag enabled and restart it on a kernel without CONFIG_CHECKPOINT_NETNS support. Signed-off-by: Dan Smith <danms@xxxxxxxxxx> --- include/linux/checkpoint.h | 3 ++- kernel/nsproxy.c | 8 ++++++-- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/include/linux/checkpoint.h b/include/linux/checkpoint.h index 0fb647b..1e7f8d3 100644 --- a/include/linux/checkpoint.h +++ b/include/linux/checkpoint.h @@ -14,6 +14,7 @@ /* checkpoint user flags */ #define CHECKPOINT_SUBTREE 0x1 +#define CHECKPOINT_NONETNS 0x2 /* restart user flags */ #define RESTART_TASKSELF 0x1 @@ -56,7 +57,7 @@ extern long do_sys_restart(pid_t pid, int fd, #define CKPT_CTX_ERROR (1 << CKPT_CTX_ERROR_BIT) /* ckpt_ctx: uflags */ -#define CHECKPOINT_USER_FLAGS CHECKPOINT_SUBTREE +#define CHECKPOINT_USER_FLAGS (CHECKPOINT_SUBTREE | CHECKPOINT_NONETNS) #define RESTART_USER_FLAGS \ (RESTART_TASKSELF | \ RESTART_FROZEN | \ diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index b0e67ff..e6a748b 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -249,7 +249,8 @@ int ckpt_collect_ns(struct ckpt_ctx *ctx, struct task_struct *t) if (ret < 0) goto out; #ifdef CONFIG_CHECKPOINT_NETNS - ret = ckpt_obj_collect(ctx, nsproxy->net_ns, CKPT_OBJ_NET_NS); + if (!(ctx->uflags & CHECKPOINT_NONETNS)) + ret = ckpt_obj_collect(ctx, nsproxy->net_ns, CKPT_OBJ_NET_NS); if (ret < 0) goto out; #endif @@ -294,7 +295,10 @@ static int do_checkpoint_ns(struct ckpt_ctx *ctx, struct nsproxy *nsproxy) goto out; h->ipc_objref = ret; #ifdef CONFIG_CHECKPOINT_NETNS - ret = checkpoint_obj(ctx, nsproxy->net_ns, CKPT_OBJ_NET_NS); + if (!(ctx->uflags & CHECKPOINT_NONETNS)) + ret = checkpoint_obj(ctx, nsproxy->net_ns, CKPT_OBJ_NET_NS); + else + ret = 0; if (ret < 0) goto out; h->net_objref = ret; -- 1.6.2.5 _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
